断路器三相不一致保护误动原因分析及对策

Malfunction Causes Analysis of Circuit-Breaker Three-Phase Inconsistent Protection and Countermeasures

针对一起220kV线路断路器发生的误跳闸事件,根据该线路故障录波示意图及现场情况,结合断路器三相不一致保护的原理,得出误动原因是断路器本体三相不一致保护时间继电器异常造成的。针对该缺陷,提出了防范其误动的措施及两种改进方案,提高三相不一致保护动作可靠性,有效保障电网安全稳定运行。

In allusion to a false-tripping event of 220 kV line circuit breaker and according to the line fault record waves schematic diagram and site situations, combined with circuit-breaker three-phase inconsistent protection principle, this paper concluded that the time relay abnormity of circuit-breaker three-phase inconsistent protection caused malfunction. Aiming at the defect, this paper raised countermeasures for malfunction and two kinds of improved schemes, which raised the reliability of three-phase inconsistent protection and ensured power grid in safe and stable operation effectively.